Maxim introduces the MAX16819/MAX16820 high-efficiency LED drivers for driving high-brightness light-emitting diodes (HB LEDs) for architectural, industrial, and automotive lighting applications. The MAX16819/MAX16820 HB LED drivers require only one external MOSFET and a small number of passive components to drive LEDs up to 3A.
Each device can drive up to 6 LEDs in series, providing output power from 1W to over 25W with an efficiency of up to 94%. Packaged in a tiny 3mm x 3mm TDFN package, the device is the most versatile in its class, with high-voltage current-sense amplifiers and switching frequencies up to 2MHz to further reduce space and component count requirements. This family of devices is highly integrated, reducing power consumption, increasing reliability, and reducing production costs. It is ideal for MR16 LEDs (instead of conventional MR16 halogen lamps) as well as automotive front and rear lighting (RCL, DRL, and Fog light).
Unlike the general-purpose buck control architecture that drives HB LEDs, the MAX16819/MAX16820 drivers use hysteretic control. With this control technology, the driver guarantees fast transient response and fast on/off control during PWM dimming, and PWM dimming technology enables a wide dimming range (up to 5000:1) or pole with dedicated DIM input High dimming switch frequency (up to 20kHz). Hysteresis control has a high input power supply rejection ratio and provides fast response to LED dimming. The device eliminates the need for control loop compensation, simplifying design and reducing component count.
The MAX16819/MAX16820's wide input voltage range (4.5V to 28V) allows the device to be optimized for use in a variety of input voltage standards, such as building and ambient lighting, and to meet the cold start and load rejection requirements of automotive applications. Operating in the automotive temperature range of -40°C to +125°C, these LED drivers are available in a tiny, 3mm x 3mm, 6-pin TDFN lead-free package with an exposed pad.
The device starts at $0.58 (1000 sheets, FOB USA). 
brief introduction: